PB1851: EARLY DEATHS IN PATIENTS WITH NEWLY DIAGNOSED ACUTE PROMYELOCYTIC LEUKEMIA: A SINGLE-CENTER RETROSPECTIVE STUDY FROM A GENERAL HOSPITAL
Authors: B. Yohannan, F. Cervoni-curet, A. Rios
Journal: HemaSphere (2022)

Background: Acute promyelocytic leukemia (APL) is a rare and distinct subtype of acute myeloid leukemia characterized by t(15;17) translocation. Although APL is considered a highly curable disease, early deaths (EDs, death within 30 days) due to coagulopathy and bleeding diathesis remain a significant challenge. ED rates in APL can be as high as 30% in a general hospital. We reviewed all cases of APL treated at Memorial Hermann Hospital (MHH) Texas Medical Center. Aims: To evaluate the ED rate and causes of EDs in newly diagnosed APL patients Methods: We retrospectively analyzed adult patients (≥18 years old) with newly diagnosed APL treated at MHH between January 2009 and December 2021. The consecutive list of patients with APL was prepared using the pharmacy electronic medical records of MHH Cancer Center. The following data were collected: Baseline demographic variables, WBC, hemoglobin, platelet count on admission, coagulation parameters, presence/absence of disseminated intravascular coagulation, bone marrow or peripheral blood molecular analysis, immunohistochemistry, cytogenetics, Sanz score and risk stratification, timing of initiation of all trans retinoid acid (ATRA), complete response (CR) rate, major adverse events during induction, and ED rate. Results: We identified 25 patients with newly diagnosed APL. All patients had flow cytometry, immunohistochemistry, cytogenetics, and molecular testing for t(15;17). The median age was 40 years (range, 20-67 years), and 52% were men. Subject races included 10 whites, 4 African Americans, 7 Hispanics, and 4 Asians. Based on Sanz risk stratification, 5 patients had low-risk, 5 had intermediate-risk, and 15 had high-risk disease. Sixteen patients presented with bleeding diathesis: 8 with intracranial hemorrhage (ICH), 6 with gastrointestinal or genitourinary bleeding, and 1 each with retinal bleed and abdominal wall hematoma. The median time to initiation of ATRA was 12 hours. Patients with high-risk APL (WBC >10,000) received idarubicin or gemtuzumab ozogamicin. Three patients died before response assessment. All 22 response-evaluable patients treated with ATRA and arsenic trioxide induction had a CR. The most common adverse events during induction therapy were febrile neutropenia (n=6), differentiation syndrome (n=5), and respiratory failure requiring mechanical ventilation (n=6); 12 required ICU admission, 4 had acute kidney injury, with 1 requiring dialysis support. Of the 8 patients who presented with ICH, 4 required emergent craniotomy, and 4 were managed conservatively. ED occurred in 3 (12%) patients: 2 died within 48 hours of admission and another between days 8 and 15. Two patients died of ICH, and one patient with subdural hematoma died from pseudomonas sepsis and multiorgan failure. Five patients developed thrombotic events: 2 each had pulmonary embolism and stroke and 1 had splenic and renal infarct. Summary/Conclusion: In our series of 25 patients, the ED rate was relatively low despite 8 of the patients presenting with ICH. Early diagnosis, timely administration of ATRA, correction of coagulopathy, critical care, and neurosurgery support are pivotal in reducing ED in APL.